In Argentina, as in other countries of Latin America, cholera has occurred in an epidemic pattern. Vibrio cholerae O1 is native to the aquatic environment, and it occurs in both culturable and viable but nonculturable (VNC) forms, the latter during interepidemic periods. This is the first report of the presence of VNC V. cholerae O1 in the estuarine and marine waters of the Río de la Plata and the Argentine shelf of the Atlantic Ocean, respectively. Employing immunofluorescence and PCR methods, we were able to detect reservoirs of V. cholerae O1 carrying the virulence-associated genes ctxA and tcpA. The VNC forms of V. cholerae O1 were identified in samples of water, phytoplankton, and zooplankton; the latter organisms were mainly the copepods Acartia tonsa, Diaptomus sp., Paracalanus crassirostris, and Paracalanus parvus. We found that under favorable conditions, the VNC form of V. cholerae can revert to the pathogenic, transmissible state. We concluded that V. cholerae O1 is a resident of Argentinean waters, as has been shown to be the case in other geographic regions of the world.Cholera reemerged in Latin America in 1991 after being absent from the continent for nearly a century. In Argentina, there have been seven epidemics since 1992, all of which were caused by El Tor biotype Vibrio cholerae O1. These cholera outbreaks occurred mainly during the summer months, and, consistent with reports from other geographic regions of the world, strains of V. cholerae O1 were isolated from water samples collected from rivers during epidemic periods. However, the microorganism could not be recovered from the environment during interepidemic periods (12).V. cholerae is a natural inhabitant of aquatic environments, and it has been found to survive for extended periods in estuarine and brackish waters (12,13,15). Furthermore, in response to extreme environmental conditions, the bacteria may enter a dormant state (7, 30), which has been designated the viable but nonculturable (VNC) state, since the organism cannot be recovered by using traditional culture media. It has been hypothesized that it is in the VNC state that V. cholerae survives in the environment during interepidemic periods. Also, interaction with plankton appears to play an important role in the ecology of the microorganism and to facilitate persistence, mainly in response to low temperatures and reduced nutrient concentrations (12,13,14,19,21).In Argentina, V. cholerae non-O1 was isolated from samples collected from the Río de la Plata in previous studies (5). Several facts, such as the seasonality of the outbreaks most likely associated with temperature shifts and plankton blooms, suggested that there are environmental reservoirs of V. cholerae. Additionally, in a recent study in which the genetic diversity of V. cholerae O1 strains isolated during the seven outbreaks that occurred in this country was analyzed, most of the cholera toxin (CT)-producing strains were found to belong to a single clonal group already recognized as the Latin American epidemic stra...

In Argentina, the annual incidence rate of reported hepatitis A disease ranged from 70.5 to 173.8 per 100,000 during 1995-2004. A single dose universal hepatitis A immunization program aimed at children aged 12 months was started in June 2005. The aim was to observe the impact of universal vaccination against hepatitis A in Argentina. A longitudinal analysis of hepatitis A rates reported in Argentina since 1995 to the National Notifiable Diseases Surveillance System (SINAVE). Incidence rates in 2007 were compared with those for the prevaccination baseline period (1998-2002), overall and by age group and geographical regions. Overall vaccine coverage in Argentina was 95% in 2006 for the single dose. After initiating the program, a sharp decrease in disease rates was observed. The annual incidence of 10.2 per 100,000 during 2007 represents 88.0% reduction with respect to the average incidence rate for the period 1998-2002 (P < 0.001). For children aged 1 year, an 83.1% reduction in disease was observed in 2007, compared with the baseline period (P < 0.001). Furthermore, a sharp decline was also observed in all other age groups 87.1% [2-4 years], 88.7% [5-9 years], 83.6% [10-14 years], 78.8% [15-49 years], 20.7% [>50 years]. Also important reductions were observed in all Argentinian regions. Following the implementation of universal hepatitis vaccination with a single dose to children at 12 months of age, hepatitis A rates have declined substantially in Argentina. Monitoring is needed to verify that vaccination continues to proceed and that low rates are sustained.

ResumenCon el objetivo de conocer la prevalencia de factores de riesgo para enfermedades cardiovasculares (ECV) y su relación con antecedentes familiares de enfermedad, se estudiaron 3.357 ingresantes al 1er año de la Universidad de Mar del Plata, en el año 1991 que completaron su revisación médica obligatoria. La prevalencia de antecedentes familiares de hipercolesterolemia, hipertensión, diabetes mellitus, obesidad, enfermedad cardiovascular (ECV) fue: 27,5%, 42,1%, 26,9 %, 27,2 % y 42,1% respectivamente. El 80,5% de los alumnos reportó al menos uno de los antecedentes familiares estudiados. La prevalencia de hipertensión (presión arterial sistólica > 140 mmHg y/o presión arterial diastólica ≥ 90 mmHg) y de hipercolesterolemia (≥ 210 mg/dl) en los participantes fue 7,0% y 14,4%. Se observó asociaciones de hipertensión con Indice de masa corporal (IMC), sexo masculino y edad. El 27,1% manifestó su condición de fumador, no presentándose diferencias entre sexos. El hábito se correlacionó positivamente con la edad y se observaron distintas prevalencias según la carrera universitaria elegida. La presencia de colesterolemia aumentada se correlacionó con la edad, el IMC y los antecedentes familiares de obesidad (OR: 1,32 IC95% = 1,06-1,64) e hipercolesterolemia (OR:1,38 IC95% = 1,10-1,69). Se detectó en un 3,7% anormalidades en el aparato cardiovascular. Se observó asociación con antecedentes de enfermedad cardíaca familiar. La prevalencia de factores de riesgo cardiovasculares hallados representan un toque de atención dada la juventud de la población considerada y muestran la necesidad de insistir en medidas educativas y de promoción de conductas preventivas.Enfermedades cardiovasculares, epidemiología. Factores de riesgo. Estudiantes. AbstractThe prevalence of cardiovascular risk factors and their relation to a self-reported family history of disease was examined in 3,357 first year university students of Mar del Plata University (Argentine). The prevalence of family disease was Rev. Saúde Pública, 30 (6): 576-86, 1996 576